2 * Copyright (c) 1997, 1998 Justin T. Gibbs.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions, and the following disclaimer,
10 * without modification, immediately at the beginning of the file.
11 * 2. The name of the author may not be used to endorse or promote products
12 * derived from this software without specific prior written permission.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
18 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * From amd64/busdma_machdep.c, r204214
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/malloc.h>
38 #include <sys/interrupt.h>
39 #include <sys/kernel.h>
43 #include <sys/memdesc.h>
44 #include <sys/mutex.h>
45 #include <sys/sysctl.h>
49 #include <vm/vm_extern.h>
50 #include <vm/vm_kern.h>
51 #include <vm/vm_page.h>
52 #include <vm/vm_map.h>
54 #include <machine/atomic.h>
55 #include <machine/bus.h>
56 #include <machine/md_var.h>
60 #define MAX_BPAGES MIN(8192, physmem/40)
70 bus_dma_filter_t *filter;
78 bus_dma_lock_t *lockfunc;
80 struct bounce_zone *bounce_zone;
86 vm_offset_t vaddr; /* kva of bounce buffer */
87 bus_addr_t busaddr; /* Physical address */
88 vm_offset_t datavaddr; /* kva of client data */
89 bus_addr_t dataaddr; /* client physical address */
90 bus_size_t datacount; /* client data count */
91 STAILQ_ENTRY(bounce_page) links;
94 int busdma_swi_pending;
97 STAILQ_ENTRY(bounce_zone) links;
98 STAILQ_HEAD(bp_list, bounce_page) bounce_page_list;
106 bus_size_t alignment;
110 struct sysctl_ctx_list sysctl_tree;
111 struct sysctl_oid *sysctl_tree_top;
114 static struct mtx bounce_lock;
115 static int total_bpages;
116 static int busdma_zonecount;
117 static STAILQ_HEAD(, bounce_zone) bounce_zone_list;
119 static SYSCTL_NODE(_hw, OID_AUTO, busdma, CTLFLAG_RD, 0, "Busdma parameters");
120 SYSCTL_INT(_hw_busdma, OID_AUTO, total_bpages, CTLFLAG_RD, &total_bpages, 0,
121 "Total bounce pages");
124 struct bp_list bpages;
129 bus_dma_segment_t *segments;
131 bus_dmamap_callback_t *callback;
133 STAILQ_ENTRY(bus_dmamap) links;
137 static STAILQ_HEAD(, bus_dmamap) bounce_map_waitinglist;
138 static STAILQ_HEAD(, bus_dmamap) bounce_map_callbacklist;
140 static void init_bounce_pages(void *dummy);
141 static int alloc_bounce_zone(bus_dma_tag_t dmat);
142 static int alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages);
143 static int reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map,
145 static bus_addr_t add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map,
146 vm_offset_t vaddr, bus_addr_t addr,
148 static void free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage);
149 static __inline int run_filter(bus_dma_tag_t dmat, bus_addr_t paddr);
152 * Return true if a match is made.
154 * To find a match walk the chain of bus_dma_tag_t's looking for 'paddr'.
156 * If paddr is within the bounds of the dma tag then call the filter callback
157 * to check for a match, if there is no filter callback then assume a match.
160 run_filter(bus_dma_tag_t dmat, bus_addr_t paddr)
167 if (dmat->filter == NULL && dmat->iommu == NULL &&
168 paddr > dmat->lowaddr && paddr <= dmat->highaddr)
170 if (dmat->filter == NULL &&
171 (paddr & (dmat->alignment - 1)) != 0)
173 if (dmat->filter != NULL &&
174 (*dmat->filter)(dmat->filterarg, paddr) != 0)
178 } while (retval == 0 && dmat != NULL);
183 * Convenience function for manipulating driver locks from busdma (during
184 * busdma_swi, for example). Drivers that don't provide their own locks
185 * should specify &Giant to dmat->lockfuncarg. Drivers that use their own
186 * non-mutex locking scheme don't have to use this at all.
189 busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
193 dmtx = (struct mtx *)arg;
202 panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
207 * dflt_lock should never get called. It gets put into the dma tag when
208 * lockfunc == NULL, which is only valid if the maps that are associated
209 * with the tag are meant to never be defered.
210 * XXX Should have a way to identify which driver is responsible here.
213 dflt_lock(void *arg, bus_dma_lock_op_t op)
215 panic("driver error: busdma dflt_lock called");
218 #define BUS_DMA_COULD_BOUNCE BUS_DMA_BUS3
219 #define BUS_DMA_MIN_ALLOC_COMP BUS_DMA_BUS4
221 * Allocate a device specific dma_tag.
224 bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
225 bus_size_t boundary, bus_addr_t lowaddr,
226 bus_addr_t highaddr, bus_dma_filter_t *filter,
227 void *filterarg, bus_size_t maxsize, int nsegments,
228 bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
229 void *lockfuncarg, bus_dma_tag_t *dmat)
231 bus_dma_tag_t newtag;
234 /* Basic sanity checking */
235 if (boundary != 0 && boundary < maxsegsz)
242 /* Return a NULL tag on failure */
245 newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF,
247 if (newtag == NULL) {
248 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
249 __func__, newtag, 0, error);
253 newtag->parent = parent;
254 newtag->alignment = alignment;
255 newtag->boundary = boundary;
256 newtag->lowaddr = trunc_page((vm_paddr_t)lowaddr) + (PAGE_SIZE - 1);
257 newtag->highaddr = trunc_page((vm_paddr_t)highaddr) + (PAGE_SIZE - 1);
258 newtag->filter = filter;
259 newtag->filterarg = filterarg;
260 newtag->maxsize = maxsize;
261 newtag->nsegments = nsegments;
262 newtag->maxsegsz = maxsegsz;
263 newtag->flags = flags;
264 newtag->ref_count = 1; /* Count ourself */
265 newtag->map_count = 0;
266 if (lockfunc != NULL) {
267 newtag->lockfunc = lockfunc;
268 newtag->lockfuncarg = lockfuncarg;
270 newtag->lockfunc = dflt_lock;
271 newtag->lockfuncarg = NULL;
274 /* Take into account any restrictions imposed by our parent tag */
275 if (parent != NULL) {
276 newtag->lowaddr = MIN(parent->lowaddr, newtag->lowaddr);
277 newtag->highaddr = MAX(parent->highaddr, newtag->highaddr);
278 if (newtag->boundary == 0)
279 newtag->boundary = parent->boundary;
280 else if (parent->boundary != 0)
281 newtag->boundary = MIN(parent->boundary,
283 if (newtag->filter == NULL) {
285 * Short circuit looking at our parent directly
286 * since we have encapsulated all of its information
288 newtag->filter = parent->filter;
289 newtag->filterarg = parent->filterarg;
290 newtag->parent = parent->parent;
292 if (newtag->parent != NULL)
293 atomic_add_int(&parent->ref_count, 1);
294 newtag->iommu = parent->iommu;
295 newtag->iommu_cookie = parent->iommu_cookie;
298 if (newtag->lowaddr < ptoa((vm_paddr_t)Maxmem) && newtag->iommu == NULL)
299 newtag->flags |= BUS_DMA_COULD_BOUNCE;
301 if (newtag->alignment > 1)
302 newtag->flags |= BUS_DMA_COULD_BOUNCE;
304 if (((newtag->flags & BUS_DMA_COULD_BOUNCE) != 0) &&
305 (flags & BUS_DMA_ALLOCNOW) != 0) {
306 struct bounce_zone *bz;
310 if ((error = alloc_bounce_zone(newtag)) != 0) {
311 free(newtag, M_DEVBUF);
314 bz = newtag->bounce_zone;
316 if (ptoa(bz->total_bpages) < maxsize) {
319 pages = atop(maxsize) - bz->total_bpages;
321 /* Add pages to our bounce pool */
322 if (alloc_bounce_pages(newtag, pages) < pages)
325 /* Performed initial allocation */
326 newtag->flags |= BUS_DMA_MIN_ALLOC_COMP;
330 free(newtag, M_DEVBUF);
334 CTR4(KTR_BUSDMA, "%s returned tag %p tag flags 0x%x error %d",
335 __func__, newtag, (newtag != NULL ? newtag->flags : 0), error);
340 bus_dma_tag_destroy(bus_dma_tag_t dmat)
342 bus_dma_tag_t dmat_copy;
350 if (dmat->map_count != 0) {
355 while (dmat != NULL) {
356 bus_dma_tag_t parent;
358 parent = dmat->parent;
359 atomic_subtract_int(&dmat->ref_count, 1);
360 if (dmat->ref_count == 0) {
361 free(dmat, M_DEVBUF);
363 * Last reference count, so
364 * release our reference
365 * count on our parent.
373 CTR3(KTR_BUSDMA, "%s tag %p error %d", __func__, dmat_copy, error);
378 * Allocate a handle for mapping from kva/uva/physical
379 * address space into bus device space.
382 bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
388 *mapp = (bus_dmamap_t)malloc(sizeof(**mapp), M_DEVBUF,
391 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
392 __func__, dmat, ENOMEM);
398 * Bouncing might be required if the driver asks for an active
399 * exclusion region, a data alignment that is stricter than 1, and/or
400 * an active address boundary.
402 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
405 struct bounce_zone *bz;
408 if (dmat->bounce_zone == NULL) {
409 if ((error = alloc_bounce_zone(dmat)) != 0)
412 bz = dmat->bounce_zone;
414 /* Initialize the new map */
415 STAILQ_INIT(&((*mapp)->bpages));
418 * Attempt to add pages to our pool on a per-instance
419 * basis up to a sane limit.
421 if (dmat->alignment > 1)
422 maxpages = MAX_BPAGES;
424 maxpages = MIN(MAX_BPAGES, Maxmem -atop(dmat->lowaddr));
425 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0
426 || (bz->map_count > 0 && bz->total_bpages < maxpages)) {
429 pages = MAX(atop(dmat->maxsize), 1);
430 pages = MIN(maxpages - bz->total_bpages, pages);
431 pages = MAX(pages, 1);
432 if (alloc_bounce_pages(dmat, pages) < pages)
435 if ((dmat->flags & BUS_DMA_MIN_ALLOC_COMP) == 0) {
437 dmat->flags |= BUS_DMA_MIN_ALLOC_COMP;
446 (*mapp)->segments = (bus_dma_segment_t *)malloc(
447 sizeof(bus_dma_segment_t) * dmat->nsegments, M_DEVBUF,
449 if ((*mapp)->segments == NULL) {
450 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
451 __func__, dmat, ENOMEM);
457 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
458 __func__, dmat, dmat->flags, error);
463 * Destroy a handle for mapping from kva/uva/physical
464 * address space into bus device space.
467 bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
469 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
470 if (STAILQ_FIRST(&map->bpages) != NULL) {
471 CTR3(KTR_BUSDMA, "%s: tag %p error %d",
472 __func__, dmat, EBUSY);
475 if (dmat->bounce_zone)
476 dmat->bounce_zone->map_count--;
478 free(map->segments, M_DEVBUF);
481 CTR2(KTR_BUSDMA, "%s: tag %p error 0", __func__, dmat);
487 * Allocate a piece of memory that can be efficiently mapped into
488 * bus device space based on the constraints lited in the dma tag.
489 * A dmamap to for use with dmamap_load is also allocated.
492 bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
498 if (flags & BUS_DMA_NOWAIT)
503 bus_dmamap_create(dmat, flags, mapp);
505 if (flags & BUS_DMA_ZERO)
508 if (flags & BUS_DMA_NOCACHE)
509 attr = VM_MEMATTR_UNCACHEABLE;
512 attr = VM_MEMATTR_DEFAULT;
516 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
517 * alignment guarantees of malloc need to be nailed down, and the
518 * code below should be rewritten to take that into account.
520 * In the meantime, we'll warn the user if malloc gets it wrong.
522 if ((dmat->maxsize <= PAGE_SIZE) &&
523 (dmat->alignment < dmat->maxsize) &&
524 dmat->lowaddr >= ptoa((vm_paddr_t)Maxmem) &&
525 attr == VM_MEMATTR_DEFAULT) {
526 *vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
529 * XXX Use Contigmalloc until it is merged into this facility
530 * and handles multi-seg allocations. Nobody is doing
531 * multi-seg allocations yet though.
532 * XXX Certain AGP hardware does.
534 *vaddr = (void *)kmem_alloc_contig(kernel_map, dmat->maxsize,
535 mflags, 0ul, dmat->lowaddr, dmat->alignment ?
536 dmat->alignment : 1ul, dmat->boundary, attr);
537 (*mapp)->contigalloc = 1;
539 if (*vaddr == NULL) {
540 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
541 __func__, dmat, dmat->flags, ENOMEM);
543 } else if (vtophys(*vaddr) & (dmat->alignment - 1)) {
544 printf("bus_dmamem_alloc failed to align memory properly.\n");
546 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d",
547 __func__, dmat, dmat->flags, 0);
552 * Free a piece of memory and it's allociated dmamap, that was allocated
553 * via bus_dmamem_alloc. Make the same choice for free/contigfree.
556 bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
559 if (!map->contigalloc)
560 free(vaddr, M_DEVBUF);
562 kmem_free(kernel_map, (vm_offset_t)vaddr, dmat->maxsize);
563 bus_dmamap_destroy(dmat, map);
564 CTR3(KTR_BUSDMA, "%s: tag %p flags 0x%x", __func__, dmat, dmat->flags);
568 _bus_dmamap_count_phys(bus_dma_tag_t dmat, bus_dmamap_t map, vm_paddr_t buf,
569 bus_size_t buflen, int flags)
574 if (map->pagesneeded == 0) {
575 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
576 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
577 dmat->boundary, dmat->alignment);
578 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
580 * Count the number of bounce pages
581 * needed in order to complete this transfer
584 while (buflen != 0) {
585 sgsize = MIN(buflen, dmat->maxsegsz);
586 if (run_filter(dmat, curaddr) != 0) {
587 sgsize = MIN(sgsize, PAGE_SIZE);
593 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
598 _bus_dmamap_count_pages(bus_dma_tag_t dmat, bus_dmamap_t map, pmap_t pmap,
599 void *buf, bus_size_t buflen, int flags)
602 vm_offset_t vendaddr;
605 if (map->pagesneeded == 0) {
606 CTR4(KTR_BUSDMA, "lowaddr= %d Maxmem= %d, boundary= %d, "
607 "alignment= %d", dmat->lowaddr, ptoa((vm_paddr_t)Maxmem),
608 dmat->boundary, dmat->alignment);
609 CTR2(KTR_BUSDMA, "map= %p, pagesneeded= %d", map, map->pagesneeded);
611 * Count the number of bounce pages
612 * needed in order to complete this transfer
614 vaddr = (vm_offset_t)buf;
615 vendaddr = (vm_offset_t)buf + buflen;
617 while (vaddr < vendaddr) {
620 sg_len = PAGE_SIZE - ((vm_offset_t)vaddr & PAGE_MASK);
621 if (pmap == kernel_pmap)
622 paddr = pmap_kextract(vaddr);
624 paddr = pmap_extract(pmap, vaddr);
625 if (run_filter(dmat, paddr) != 0) {
626 sg_len = roundup2(sg_len, dmat->alignment);
631 CTR1(KTR_BUSDMA, "pagesneeded= %d\n", map->pagesneeded);
636 _bus_dmamap_reserve_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int flags)
639 /* Reserve Necessary Bounce Pages */
640 mtx_lock(&bounce_lock);
641 if (flags & BUS_DMA_NOWAIT) {
642 if (reserve_bounce_pages(dmat, map, 0) != 0) {
643 mtx_unlock(&bounce_lock);
647 if (reserve_bounce_pages(dmat, map, 1) != 0) {
648 /* Queue us for resources */
649 STAILQ_INSERT_TAIL(&bounce_map_waitinglist,
651 mtx_unlock(&bounce_lock);
652 return (EINPROGRESS);
655 mtx_unlock(&bounce_lock);
661 * Add a single contiguous physical range to the segment list.
664 _bus_dmamap_addseg(bus_dma_tag_t dmat, bus_dmamap_t map, bus_addr_t curaddr,
665 bus_size_t sgsize, bus_dma_segment_t *segs, int *segp)
667 bus_addr_t baddr, bmask;
671 * Make sure we don't cross any boundaries.
673 bmask = ~(dmat->boundary - 1);
674 if (dmat->boundary > 0) {
675 baddr = (curaddr + dmat->boundary) & bmask;
676 if (sgsize > (baddr - curaddr))
677 sgsize = (baddr - curaddr);
681 * Insert chunk into a segment, coalescing with
682 * previous segment if possible.
687 segs[seg].ds_addr = curaddr;
688 segs[seg].ds_len = sgsize;
690 if (curaddr == segs[seg].ds_addr + segs[seg].ds_len &&
691 (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
692 (dmat->boundary == 0 ||
693 (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
694 segs[seg].ds_len += sgsize;
696 if (++seg >= dmat->nsegments)
698 segs[seg].ds_addr = curaddr;
699 segs[seg].ds_len = sgsize;
707 * Utility function to load a physical buffer. segp contains
708 * the starting segment on entrace, and the ending segment on exit.
711 _bus_dmamap_load_phys(bus_dma_tag_t dmat,
713 vm_paddr_t buf, bus_size_t buflen,
715 bus_dma_segment_t *segs,
723 segs = map->segments;
725 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
726 _bus_dmamap_count_phys(dmat, map, buf, buflen, flags);
727 if (map->pagesneeded != 0) {
728 error = _bus_dmamap_reserve_pages(dmat, map, flags);
736 sgsize = MIN(buflen, dmat->maxsegsz);
737 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
738 sgsize = MIN(sgsize, PAGE_SIZE);
739 curaddr = add_bounce_page(dmat, map, 0, curaddr,
742 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
753 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
757 * Utility function to load a linear buffer. segp contains
758 * the starting segment on entrance, and the ending segment on exit.
761 _bus_dmamap_load_buffer(bus_dma_tag_t dmat,
763 void *buf, bus_size_t buflen,
766 bus_dma_segment_t *segs,
775 segs = map->segments;
777 if ((dmat->flags & BUS_DMA_COULD_BOUNCE) != 0) {
778 _bus_dmamap_count_pages(dmat, map, pmap, buf, buflen, flags);
779 if (map->pagesneeded != 0) {
780 error = _bus_dmamap_reserve_pages(dmat, map, flags);
786 vaddr = (vm_offset_t)buf;
789 bus_size_t max_sgsize;
792 * Get the physical address for this segment.
794 if (pmap == kernel_pmap)
795 curaddr = pmap_kextract(vaddr);
797 curaddr = pmap_extract(pmap, vaddr);
800 * Compute the segment size, and adjust counts.
802 max_sgsize = MIN(buflen, dmat->maxsegsz);
803 sgsize = PAGE_SIZE - ((vm_offset_t)curaddr & PAGE_MASK);
804 if (map->pagesneeded != 0 && run_filter(dmat, curaddr)) {
805 sgsize = roundup2(sgsize, dmat->alignment);
806 sgsize = MIN(sgsize, max_sgsize);
807 curaddr = add_bounce_page(dmat, map, vaddr, curaddr,
810 sgsize = MIN(sgsize, max_sgsize);
813 sgsize = _bus_dmamap_addseg(dmat, map, curaddr, sgsize, segs,
824 return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
828 __bus_dmamap_waitok(bus_dma_tag_t dmat, bus_dmamap_t map,
829 struct memdesc *mem, bus_dmamap_callback_t *callback,
833 if (dmat->flags & BUS_DMA_COULD_BOUNCE) {
836 map->callback = callback;
837 map->callback_arg = callback_arg;
842 _bus_dmamap_complete(bus_dma_tag_t dmat, bus_dmamap_t map,
843 bus_dma_segment_t *segs, int nsegs, int error)
848 memcpy(map->segments, segs, map->nsegs*sizeof(segs[0]));
849 if (dmat->iommu != NULL)
850 IOMMU_MAP(dmat->iommu, map->segments, &map->nsegs,
851 dmat->lowaddr, dmat->highaddr, dmat->alignment,
852 dmat->boundary, dmat->iommu_cookie);
855 memcpy(segs, map->segments, map->nsegs*sizeof(segs[0]));
857 segs = map->segments;
863 * Release the mapping held by map.
866 _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
868 struct bounce_page *bpage;
871 IOMMU_UNMAP(dmat->iommu, map->segments, map->nsegs, dmat->iommu_cookie);
875 while ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
876 STAILQ_REMOVE_HEAD(&map->bpages, links);
877 free_bounce_page(dmat, bpage);
882 _bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
884 struct bounce_page *bpage;
886 if ((bpage = STAILQ_FIRST(&map->bpages)) != NULL) {
888 * Handle data bouncing. We might also
889 * want to add support for invalidating
890 * the caches on broken hardware
892 CTR4(KTR_BUSDMA, "%s: tag %p tag flags 0x%x op 0x%x "
893 "performing bounce", __func__, op, dmat, dmat->flags);
895 if (op & BUS_DMASYNC_PREWRITE) {
896 while (bpage != NULL) {
897 if (bpage->datavaddr != 0)
898 bcopy((void *)bpage->datavaddr,
899 (void *)bpage->vaddr,
902 physcopyout(bpage->dataaddr,
903 (void *)bpage->vaddr,
905 bpage = STAILQ_NEXT(bpage, links);
907 dmat->bounce_zone->total_bounced++;
910 if (op & BUS_DMASYNC_POSTREAD) {
911 while (bpage != NULL) {
912 if (bpage->datavaddr != 0)
913 bcopy((void *)bpage->vaddr,
914 (void *)bpage->datavaddr,
917 physcopyin((void *)bpage->vaddr,
918 bpage->dataaddr, bpage->datacount);
919 bpage = STAILQ_NEXT(bpage, links);
921 dmat->bounce_zone->total_bounced++;
927 init_bounce_pages(void *dummy __unused)
931 STAILQ_INIT(&bounce_zone_list);
932 STAILQ_INIT(&bounce_map_waitinglist);
933 STAILQ_INIT(&bounce_map_callbacklist);
934 mtx_init(&bounce_lock, "bounce pages lock", NULL, MTX_DEF);
936 SYSINIT(bpages, SI_SUB_LOCK, SI_ORDER_ANY, init_bounce_pages, NULL);
938 static struct sysctl_ctx_list *
939 busdma_sysctl_tree(struct bounce_zone *bz)
941 return (&bz->sysctl_tree);
944 static struct sysctl_oid *
945 busdma_sysctl_tree_top(struct bounce_zone *bz)
947 return (bz->sysctl_tree_top);
951 alloc_bounce_zone(bus_dma_tag_t dmat)
953 struct bounce_zone *bz;
955 /* Check to see if we already have a suitable zone */
956 STAILQ_FOREACH(bz, &bounce_zone_list, links) {
957 if ((dmat->alignment <= bz->alignment)
958 && (dmat->lowaddr >= bz->lowaddr)) {
959 dmat->bounce_zone = bz;
964 if ((bz = (struct bounce_zone *)malloc(sizeof(*bz), M_DEVBUF,
965 M_NOWAIT | M_ZERO)) == NULL)
968 STAILQ_INIT(&bz->bounce_page_list);
970 bz->reserved_bpages = 0;
971 bz->active_bpages = 0;
972 bz->lowaddr = dmat->lowaddr;
973 bz->alignment = MAX(dmat->alignment, PAGE_SIZE);
975 snprintf(bz->zoneid, 8, "zone%d", busdma_zonecount);
977 snprintf(bz->lowaddrid, 18, "%#jx", (uintmax_t)bz->lowaddr);
978 STAILQ_INSERT_TAIL(&bounce_zone_list, bz, links);
979 dmat->bounce_zone = bz;
981 sysctl_ctx_init(&bz->sysctl_tree);
982 bz->sysctl_tree_top = SYSCTL_ADD_NODE(&bz->sysctl_tree,
983 SYSCTL_STATIC_CHILDREN(_hw_busdma), OID_AUTO, bz->zoneid,
985 if (bz->sysctl_tree_top == NULL) {
986 sysctl_ctx_free(&bz->sysctl_tree);
987 return (0); /* XXX error code? */
990 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
991 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
992 "total_bpages", CTLFLAG_RD, &bz->total_bpages, 0,
993 "Total bounce pages");
994 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
995 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
996 "free_bpages", CTLFLAG_RD, &bz->free_bpages, 0,
997 "Free bounce pages");
998 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
999 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1000 "reserved_bpages", CTLFLAG_RD, &bz->reserved_bpages, 0,
1001 "Reserved bounce pages");
1002 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1003 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1004 "active_bpages", CTLFLAG_RD, &bz->active_bpages, 0,
1005 "Active bounce pages");
1006 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1007 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1008 "total_bounced", CTLFLAG_RD, &bz->total_bounced, 0,
1009 "Total bounce requests");
1010 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1011 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1012 "total_deferred", CTLFLAG_RD, &bz->total_deferred, 0,
1013 "Total bounce requests that were deferred");
1014 SYSCTL_ADD_STRING(busdma_sysctl_tree(bz),
1015 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1016 "lowaddr", CTLFLAG_RD, bz->lowaddrid, 0, "");
1017 SYSCTL_ADD_INT(busdma_sysctl_tree(bz),
1018 SYSCTL_CHILDREN(busdma_sysctl_tree_top(bz)), OID_AUTO,
1019 "alignment", CTLFLAG_RD, &bz->alignment, 0, "");
1025 alloc_bounce_pages(bus_dma_tag_t dmat, u_int numpages)
1027 struct bounce_zone *bz;
1030 bz = dmat->bounce_zone;
1032 while (numpages > 0) {
1033 struct bounce_page *bpage;
1035 bpage = (struct bounce_page *)malloc(sizeof(*bpage), M_DEVBUF,
1040 bpage->vaddr = (vm_offset_t)contigmalloc(PAGE_SIZE, M_DEVBUF,
1045 if (bpage->vaddr == 0) {
1046 free(bpage, M_DEVBUF);
1049 bpage->busaddr = pmap_kextract(bpage->vaddr);
1050 mtx_lock(&bounce_lock);
1051 STAILQ_INSERT_TAIL(&bz->bounce_page_list, bpage, links);
1055 mtx_unlock(&bounce_lock);
1063 reserve_bounce_pages(bus_dma_tag_t dmat, bus_dmamap_t map, int commit)
1065 struct bounce_zone *bz;
1068 mtx_assert(&bounce_lock, MA_OWNED);
1069 bz = dmat->bounce_zone;
1070 pages = MIN(bz->free_bpages, map->pagesneeded - map->pagesreserved);
1071 if (commit == 0 && map->pagesneeded > (map->pagesreserved + pages))
1072 return (map->pagesneeded - (map->pagesreserved + pages));
1073 bz->free_bpages -= pages;
1074 bz->reserved_bpages += pages;
1075 map->pagesreserved += pages;
1076 pages = map->pagesneeded - map->pagesreserved;
1082 add_bounce_page(bus_dma_tag_t dmat, bus_dmamap_t map, vm_offset_t vaddr,
1083 bus_addr_t addr, bus_size_t size)
1085 struct bounce_zone *bz;
1086 struct bounce_page *bpage;
1088 KASSERT(dmat->bounce_zone != NULL, ("no bounce zone in dma tag"));
1090 bz = dmat->bounce_zone;
1091 if (map->pagesneeded == 0)
1092 panic("add_bounce_page: map doesn't need any pages");
1095 if (map->pagesreserved == 0)
1096 panic("add_bounce_page: map doesn't need any pages");
1097 map->pagesreserved--;
1099 mtx_lock(&bounce_lock);
1100 bpage = STAILQ_FIRST(&bz->bounce_page_list);
1102 panic("add_bounce_page: free page list is empty");
1104 STAILQ_REMOVE_HEAD(&bz->bounce_page_list, links);
1105 bz->reserved_bpages--;
1106 bz->active_bpages++;
1107 mtx_unlock(&bounce_lock);
1109 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1110 /* Page offset needs to be preserved. */
1111 bpage->vaddr |= vaddr & PAGE_MASK;
1112 bpage->busaddr |= vaddr & PAGE_MASK;
1114 bpage->datavaddr = vaddr;
1115 bpage->dataaddr = addr;
1116 bpage->datacount = size;
1117 STAILQ_INSERT_TAIL(&(map->bpages), bpage, links);
1118 return (bpage->busaddr);
1122 free_bounce_page(bus_dma_tag_t dmat, struct bounce_page *bpage)
1124 struct bus_dmamap *map;
1125 struct bounce_zone *bz;
1127 bz = dmat->bounce_zone;
1128 bpage->datavaddr = 0;
1129 bpage->datacount = 0;
1130 if (dmat->flags & BUS_DMA_KEEP_PG_OFFSET) {
1132 * Reset the bounce page to start at offset 0. Other uses
1133 * of this bounce page may need to store a full page of
1134 * data and/or assume it starts on a page boundary.
1136 bpage->vaddr &= ~PAGE_MASK;
1137 bpage->busaddr &= ~PAGE_MASK;
1140 mtx_lock(&bounce_lock);
1141 STAILQ_INSERT_HEAD(&bz->bounce_page_list, bpage, links);
1143 bz->active_bpages--;
1144 if ((map = STAILQ_FIRST(&bounce_map_waitinglist)) != NULL) {
1145 if (reserve_bounce_pages(map->dmat, map, 1) == 0) {
1146 STAILQ_REMOVE_HEAD(&bounce_map_waitinglist, links);
1147 STAILQ_INSERT_TAIL(&bounce_map_callbacklist,
1149 busdma_swi_pending = 1;
1150 bz->total_deferred++;
1151 swi_sched(vm_ih, 0);
1154 mtx_unlock(&bounce_lock);
1161 struct bus_dmamap *map;
1163 mtx_lock(&bounce_lock);
1164 while ((map = STAILQ_FIRST(&bounce_map_callbacklist)) != NULL) {
1165 STAILQ_REMOVE_HEAD(&bounce_map_callbacklist, links);
1166 mtx_unlock(&bounce_lock);
1168 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_LOCK);
1169 bus_dmamap_load_mem(map->dmat, map, &map->mem,
1170 map->callback, map->callback_arg,
1172 (dmat->lockfunc)(dmat->lockfuncarg, BUS_DMA_UNLOCK);
1173 mtx_lock(&bounce_lock);
1175 mtx_unlock(&bounce_lock);
1179 bus_dma_tag_set_iommu(bus_dma_tag_t tag, struct device *iommu, void *cookie)
1182 tag->iommu_cookie = cookie;